Alcoa Looks to the Sky to Cut its Mine's Energy Footprint

Sometimes environmental wins can be found in unlikely places. And when you're a mining company, looking up in the sky is about as unlikely as it gets.

Jamalco Operations, a mining subsidiary majority-owned by Alcoa, looked up to dig out a big win in Jamaica. Jamalco, which mines bauxite and processes it into alumina, announced that it's hauled 10 million tons of bauxite in two years using a unique, sustainable transport system.

The Rope Conveyor, or RopeCon, system (pictured above and at the bottom of this article) at the Mount Oliphant Mine is a an AC motor-powered cable conveyor system just over two miles long, running between the mine and a rail station at the base of the 843-foot Mount Oliphant.

Alcoa said it has saved about $1.5 million in operating costs since the system launched in 2007, through the following green features:

• Once the system is loaded at the top and begins its descent, its drive uses regenerative, constant braking to generate 1,200 kW per hour to power the mine and feed excess electricity fed back into Jamaica's grid. That's the equivalent of avoiding of the CO2 emissions from using 93 gallons of gasoline.
• It operates above ground, which reduces the system's physical footprint.
• Using the RopeCon system means Jamalco avoids 1,200 truck trips and the associated dust, noise and carbon emissions each day.

Jamalco's RopeCon system is just one of many sustainability projects its parent company has put in place in recent years to help it meet its sustainability goals -- some of which goals it achieved much earlier than it expected.

Earlier this year the company said it reduced its carbon intensity by 22 percent below 2005 levels, better than the 20 percent reduction it hoped to achieve by 2020. It also cut water-use intensity by 19 percent, well above its 10 percent goal.

While Alcoa is considering whether to re-calibrate its sustainability goals, it is still aiming to reduce greenhouse gas emissions by 30 percent by 2030. The company is also a member of a consortium working to develop the Global Reporting Initiative's G4 framework, due out in 2013. One of Alcoa's goals for the new environmental reporting framework is to have it include lifecycle assessment data of company products and services.

Jamalco, of which Alcoa owns 55 percent in partnership with the Jamaican government, has its own sustainability goals. According to its 2009 Sustainability Report [PDF], compared to 2008 operations:

• It reduced by 14 percent the amount of oil used to produce a ton of alumina -- the raw material needed to make aluminum, Alcoa's main product.
• It also reduced greenhouse gas emissions by 12 percent in 2009 over 2008 levels, although it increased production to more than 1.4 million metric tons of alumina.
• Sulphur dioxide emissions dropped slightly while emissions of nitrogen oxide and volatile organic compounds remained steady as production increased.
• The amount of waste Jamalco sent to landfill fell by almost 2 million metric tonnes.

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